What is virtual memory, if OS didt have that concept What
are the problems can arise?

Answers were Sorted based on User's Feedback



What is virtual memory, if OS didt have that concept What are the problems can arise?..

Answer / anshul.jain

Hi,
Virtual Memory is a concept in which user of a system feels
to have a large physical memory(Main) that actually does
not available.
for example U feel unlimited memory(Main) thougn u have
only in MB's.

If OS did not have this concept then user has to manage the
memory and in deed can run only a few program at a time.
It means here comes a limit on the efficiency of the system.

byeeeeeeeeeeeeeeeeee.

Is This Answer Correct ?    25 Yes 12 No

What is virtual memory, if OS didt have that concept What are the problems can arise?..

Answer / @pravin.08

hi!
virtual memory is a technique that allows the execution of
processes that are not completely in physical memory,
and the size of program may be larger than the physical memory!
OS without this technique needs the whole program to be in
main memory to execute,other processes need to wait for the
execution of currently executing program while OS with
virtual memory technique pages are swap in memory on
demand,this on demand paging causes efficient use of system
resources.

Is This Answer Correct ?    11 Yes 0 No

What is virtual memory, if OS didt have that concept What are the problems can arise?..

Answer / kamlesh sancheti

Virtual Memory is a cost effective solution to slake the
thirst of memory hungry applications for a seamless
experience with your operating system. To understand the
concept of virtual memory you need a little knowledge about
the memory organization and working. There are basically two
types of memory you need to know. Random Access Memory (RAM)
is faster but costly. Memory like hard disk is slower but
relatively cheaper. Virtual memory is a stratagem to utilize
the hard drive memory to achieve enhanced performance from
the random access memory.

Whenever you run multiple programs/applications in your
desktop, you will be working on only a portion of a
particular application at an instant. Therefore it is a
waste of resource to load the entire memory required for a
particular application into the limited size random access
main memory. In a virtual memory environment each page of a
process is brought to main memory only when it is needed on
demand.


Data is stored in any memory in the form of binary digits.
The operating system handles memory management in the form
of chunks of memory called pages. A page is nothing but a
contiguous block of memory. One process might require
multiple pages of memory but only a few pages might be
active at a time. Virtual memory uses a technique called
demand paging to effectively use the available RAM memory.
Every page has an address which may be a virtual or logical
address. The main memory is divided into equal size chunks
called page frames and each page frame has a unique physical
address. So whenever a page needs to be accessed, the
operating system has to translate the virtual address into a
physical address and this is done by a Memory Management
Unit (MMU) with the help of mapping in a page table. The
virtual address corresponding to a page is mapped to a
physical address corresponding to a page frame in main
memory. Whenever a page is not in memory the operating
system fetches the page from hard disk in response to a page
fault exception. The operating system usually makes a
prediction based on past history using intelligent
algorithms regarding those pages that are least likely to be
needed again and places them in the hard disk.

Is This Answer Correct ?    9 Yes 0 No

What is virtual memory, if OS didt have that concept What are the problems can arise?..

Answer / sanjeev pathak

allows the execution of process that may not be complete in
memory

Is This Answer Correct ?    6 Yes 0 No

What is virtual memory, if OS didt have that concept What are the problems can arise?..

Answer / n.v.l.n.sivaramakrishna

virtual memory is not only used for applications. Latest
operations works using default virtual memory size
allocated by the operating system at the time of
installation. This will depends on total memory we are
having in you system or server.

The best way is allocation of un-used partition for page
file purpose. Be sure no boday is accessing the
partition. This will increase system or server performance.

Don't remove pagefile settings this may cause system or
server crash.


regards,
sivaramakrishna.

Is This Answer Correct ?    11 Yes 6 No

What is virtual memory, if OS didt have that concept What are the problems can arise?..

Answer / gyanendra pratap singh

hi
virtual memory is depend upon your processor if u r using
32 bit of processor the n we can addressed the 2 to the
power 32 adresses which is 4GB space . suppose u have 1 GB
of RAM then u addressed 1.5 virtual memory if u want to
maintain ur system performance , bcz if u assign whole 4 GB
address space then ur pc performance becomes slow , why bcz
memory of ram in mainly consist of two parts one is in
which process executed and one in which we make the virtual
page pages in secondry memory , which is called paging , if
u assign all the memory for paging then process space
memory is become less because of less memory is process
space too much swaping of processes is occurred so system
performance becomes low..

In one word virtual memory is present in secondry memory
(hard disk) which is mapped by the ram presented in the
system , because of it virtual memory is faster than
secondry memory and slower than RAM .
If the O S did not have that concept , the large memory
size process executing slowly and two much swapping iis
done by the O S ..

Is This Answer Correct ?    7 Yes 2 No

Post New Answer

More Operating Systems General Concepts Interview Questions

What is the full form itc?

0 Answers  


Explain a system in safe state?

0 Answers  


Considering notepad/IE or any other thing as process, What will happen if you start notepad or IE 3 times ? Where three processes are started or three threads are started?

0 Answers  


Tell me operating systems used in mobile.

0 Answers   Tech Mahindra,


Can I install 64 bit on x86?

0 Answers  






How do I know if my os is corrupted?

0 Answers  


What is called a page fault?

0 Answers  


What is the trtw/trwt timing?

0 Answers  


Can a laptop have 32gb of ram?

0 Answers  


How do I find my hidden files?

0 Answers  


When does stack (process stack) overflow? What are the remedies?

0 Answers   Adobe,


What is MUTEX ?

4 Answers  


Categories